Buttonhole-sewing machine



Dec 4, 1928.

A. F. CARLSON BUTTONHOLE SEWING MACHINE Filed Dec. 18, 1926 2 Sheets-Sheet lnvenTor. Axel F Carlson by/a/JMkW Dec. 4, 1928. 1,694,093

A. F. CARLSQN BUTTONHOLE SEWING MACHINE Filed Dec. 18, 1926 2 Sheets-Sheet 2 Fig.2.

lnvenTor.

Axel F Curl-son M WA/M ATTyS.

Patented Dec. 4, 192 8.

UNITED STATES PATENT OFFICE.

AXEL F. CARLSON, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNOR TO THE REECE BUT- TON HOLE MACHINE COMPANY, 013 BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.

BUTTONHOLE-SEWING MACHINE.

Application filed December 18, 1926. Serial No. 155,621.

This invention relates to buttonhole sewing machines of that type in which the needle bar is given a lateral jogging movement in timed relation with the needle thrusts so that the needle thrusts are made alternately at the slit of the buttonhole and at a distance back from the slit.

One of the objects of the invention is to provide an improved means for giving the needle its lateral vibratory movement which will permit of an increased speed of operation.

Another obj ectof the invention is to provide an improved needle jogging mechanism which is constructed so that any wear which occurs in the operative parts will be automatically compensated for thus preventing the development of any loosencss in the parts due to wear.

Other features of the invention are to improve generally the neeclle-jogg;ng mechanism of a sewing machine in particulars which will be more fully hereinafter set forth.

In order to give an understanding of the invention I have illustrated in the drawings a selected embodiment thereof which will now be described after which the novel features will be pointed out in the appended claims.

Fig. 1 is a side view of a portion of a sewing machine embodying my invention;

Fig. 2 is a front view of the head with a portion broken out;

Fig. 3 is a section on the line 33, Fig. 2. v

The sewing machine illustrated in the drawings is similar to that shown in United States Patent No. 1,437,847, dated December 5th, 1922. Said machine is provided with the usual bed 1 and with the head or overhanging arm 2 in which the needle bar 3 reciprocates, said needle bar carrying the upper needle 4 which during its reciprocation penetrates the work. a

This needle bar may be given its vertical reciprocation by any suitable means, the means herein illustrated being a lever 5 which is pivoted to the frame or head 2 at 6 and is connected at its forward end to the needle bar as shown at 7, the opposite or rear end of said lever being connected to an eccentric strap 8 which surrounds an eccentric 9 on the shaft 10. This shaft is driven from a driving shaft 11 by means of intermeshing what similar to that shown in above-men tioned Patent N 0. 1,437,847 but which is improved thereover in order to provide for increased speed ofoperation and to reduce vibration.

The needle bar 3 extends axially through a sleeve member 14 which has a lateral vibrating movement in timed relation to the reciprocations of the needle. This sleeve member 14 extends through a guiding member which is provided with two depending ears or guides 16 between which the lower portion of the sleeve member-14 is received. This lower. portion of the sleeve member is preferably fiat faced as shown in Fig. 3 and each of two opposite faces has formed therein an inclined cam groove 17 in which is received projections or fins 18 carried by the ears 16. The sleeve member 14 is given a vertical reciprocating motion through the guiding member and as it moves up and down relative to the projections 18 which occupy the inclined grooves 17 the sleeve 14 will be given a lateral movement as indicated by the full and dotted lines Fig. 2. l Vhen the sleeve moves upwardly it will be forced or cammed to the right into the dotted line position Fig. 2 and when the sleeve moves downwardly it will be forced to the left into the full line position all as described in the above-mentioned Patent No. 1,437,847.

In the construction herein shown the guiding memberis in the form of a gear which is rotated at the end of .the buttonhole thereby to form the eye thereof, this rotation be. ing effected in usual. manner by means of a gear segment 19 which is rigid with an oscillating shaft 20.

The sleeve member 14 is given avertical reciprocating motion in timed relation with the reciprocations of the needle but at onehalf the speed thereof and the means herein shown for thus reciprocating the sleeve is similar to that illustrated in the above-mentioned patent. Said sleeve is connected at its upper end above the gear as shown at 21 to one end of a lever 22 pivoted at 23to the frame,the other end of said lever being connected by a link 24 to a yoke member 25 pivoted at 26 and which embraces a cam 27 carried by the shaft 11. Through this connection, which is the same as is illustrated in said Patent No. 1,437,847 the sleeve is given a vertical reciprocating motion at one-half the speed of the reciprocating movement of the needle bar 3.

In the construction shown in the abovementioned patent the projections which operate in the cam grooves 17 of the sleeve member are carried by blocks which are mounted in the ears 16, said blocks being held in their adjusted position by retainers. \Vith this construction any wear which occurs between the projections and the grooves in the sleeve member will cause looseness of the parts which not only results in unnecessary vib '2.- tion and noise but also affects the accuracy of the operation because to form perfect stitching it is desirable that the needle should be positively guided at all points in its movement.

In the present invention I have provided an improvement whereby any wear which occurs between the projections 18 and the grooves 17 will be automatically compensated for thus preventing the development of any looseness in the parts and any consequent unnecessary noise and also providing for accurately guid ing the needle at all times.

n the present invention the ears 16 are formed so that they fit loosely and freely against the grooved sides of the sleeve member 14 as shown at 28. The projections 18 are tapered as are the walls of the grooves 17 but each projection is of a length shorter than the depth of the corresponding groove so that the end of the projection is spaced from the bottom of the grooves as clearly seen in Fig. 3. These projections 18 are formed on the ends of blocks 29 as in the above-mentioned patent which are received in openings in the ears 16. In the present invention, however, these blocks 29 are acted upon by springs which yieldingly hold the projections 18 in the grooves 17. These springs are indicated at 30.

The blocks 29 are provided with recesses 31 in which the springs are received and the springs are backed by the depending portions or ears 32 of retainers 33 which are adjustably secured in the ears 16 and are retained in adjusted position by the set screws 34. l

With this construction any wear which occurs between the sides of the projections 18 and the side walls of the groove 17 will be automatically compensated for, for as such wear occurs the springs 30 will urge the blocks 29 forwardly so as to maintain a tight fit between the projections and the grooves, this being possible because the grooves are deep enough to permit the projections to be advanced into them somewhat as wear occurs. Furthermore, the construction by which the grooved sides of the sleeve member 14 have a loose sliding fit between the ears 16 serves to hold the sleeve from any lateral movement in the direction of the axis of the ears. The sleeve, however, is aliowed to vibrate freely in a direction at right angles to the axial line of the cars 16 as shown by the dotted lines Figs. 2 and 3.

In sewing machines of this type the upper end of the needle bar is swivelled in the overhanging arm 2 so that the needle bar swings from its upper end during its lateral vibration. In the above-mentioned Patent No. 1,437,841? this swivel connection was in the form of a ball mounted on the sleeve which was received in a socket in the overhanging arm. In my present invention I have provideda special form of roller bearing for this purpose. This roller bearing comprises an outer annular race 35 which is set into the head 2 and an inner annular race 36 and balls 87 confined between the races. The track on the outer race 35 is curved so as to permit the inner race 36 to tip slightly wit-h reference to the outer race. The inner race carries a sleeve 38 through which the needle bar 3 reciprocates. This makes a very steady bearing for the upper end of the needle bar which at the same time permits it to swing as requircd for the 'ogging movement.

By means 0 these improvements it is possible to increase the speed of operation of the machine without developing any undue vibration and any wear which may occur between the projections 18 and the grooves 17 is automatically compensated for thus avoiding the development of any looseness in the parts.

I claim:

1. In a sewing machine, the combination with a vertically-reciprocating needle bar, of a vertically-reciprocating sleeve member through which the needle bar reciprocates and by which it is guided, said sleeve member having inclined grooves on two opposite sides, the side walls of each roove converging term the mouth toward the bottom, a guiding member having two guiding portions engaging opposite sides of the sleeve member, pro ections earned by said guldmg portions and fitting the grooves of the sleeve member, the end of each projection being spaced from the bottom of the corresponding groove, springs acting on said projections and yieldingly holding them in operative engagement with the sleeve member, and means to reciprocate both the needle bar and the sleeve member vertically but at different speeds.

In a sewing machine, the combination with a vertically-reciprocating needle bar, of a vertically-reciprocating sleeve member through which the needle bar extends and by which it is guided, said sleeve member having inclined grooves on two opposed faces, a guiding member having guiding portions engaging the grooved sides of the sleeve member, projections carried by said guiding p0rtions and operating in the inclined grooves, springs acting on said projections and yieldingly holding them in operative position, and means to reciprocate both the needle bar and the sleeve but at different speeds.

3. In a sewing machine, the combination with a vertically-reciprocating needle bar, of a vertically-reeiprocating sleeve member through which the needle bar extends and by which it is guided, said sleeve member having inclined grooves on two opposed faces, each groove having inclined side walls, a guiding member having guiding portions engaging the opposed grooved faces of the sleeve member, a block carried by each guiding portion and provided with a tapered projection entering one of the grooves of the sleeve member, the end of each projection being wider than the bottom of the groove so that the end of the projection is spaced from the bottom of the groove, each block having a spring-receiving recess, a spring in each recess, a retainer forming a backing for each spring, said springs yieldingly holding the projections in the grooves, and means to reciprocate both the needle bar and the sleeve but at different speeds.

l. In a sewing machine, the combination with a vertically-reciprocating needle bar, of a vertically-reciprocating sleeve member through which the needle bar extends and by which it is guided, said sleeve member having inclined I grooves on opposed faces, each. groove having inclined side walls and being narrower at the bottom than at the mouth, a guiding member having two guiding portions, tapering projections supported by said guiding portions and entering said grooves, each projection having such dimension that when it is operating in the groove the end of the projection will be spaced from the bottom of the groove, and springs acting on the projections and yieldingly holding them in operative position, whereby the springs will maintain a tight running fit between the projections and the grooves as wear occurs.

5. In a sewing machine, the combination with a head, of a vertically-reciprocating needle bar, a bearing sleeve through which the upper end of the needle bar extends, a ball bearing between said sleeve and frame comprising an inner annular race member fast on the sleeve, an outer race member fast in the frame, and balls between said race members, said inner race member being capable of tipping relative to the outer race member, a gear member carried by said frame, and provided with guiding portions, a sleeve member extending through the gear member and provided on opposite faces with inclined grooves, the lower end of the needle bar reciprocating through said sleeve member, projections carried by the guiding portions and engaging the grooves of the sleeve member, and springs acting on said projections and yieldingly holding them in operative position.

In testimony whereof, I have signed my name to this specification.

AXEL F. CARLSON. 

